Answer:

Explanation:
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In this case, for such formation of sulfur hexafluoride, the standard enthalpy of formation is -1220.47 kJ/mol (data extracted from NIST database). Next, we compute the moles in 10.0 grams of sulfur hexafluoride as shown below:

Next, for the given energy, we compute the total heat that is liberated:

Finally, we conclude such symbol has sense since negative heat is related with liberated heat.
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Carbohydrates,Lipids,Proteins,Nucleic acids,<span>Organic Compounds</span>
Explanation:
As the name suggests, a single molecule of Dinitrogen Pentoxide will have 2 (di) nitrogen atoms and 5 (Pent) oxygen atoms.
Density will be mass/volume= 0.2/500 = 0.0004